Method and device for saving energy in indoor cooling and heating

ABSTRACT

Energy saving in indoor air conditioning is achieved by combining indoor air vertical convection producing means and indoor air conditioning means.  
     A fan for performing suction and exhaust of the air for vertically circulating the indoor air through suction and exhaust ports provided on upper and lower parts of a room is operated or stopped, according to a difference in temperatures detected on the upper and lower parts of the room, and the output of the fan at the time of operation is increased or decreased according thereto, so as to prevent a loss of energy such that warm air is accumulated on the upper part in the room, and cool air is accumulated on the lower part of the room.  
     Further, the operation or suspension of an air conditioner installed indoors, and the amount of energy consumed at the time of operating the air conditioner is controlled depending on a difference between a temperature detected in the room and a preset indoor temperature.  
     By combining the indoor air vertical convection producing means and the indoor air conditioning means, room temperature can be controlled efficiently with less energy consumption.

TECHNICAL FIELD

[0001] The present invention relates to a method and apparatus for saving energy in indoor air conditioning, in order to reduce an energy loss as much as possible, at the time of indoor air conditioning in, for example, ordinary houses, offices, stores, assembly halls, public office buildings, schools, hospitals, factories and greenhouses.

BACKGROUND ART

[0002] Conventional air conditioners are normally operated or stopped, when the indoor temperature detected by a temperature sensor provided in a suitable place in a room (for example, near the air conditioner) has reached a preset indoor temperature. Therefore, it is known that a loss of energy is conspicuous, such that even when the indoor temperature detected by the temperature sensor has reached the set indoor temperature, if heating is continued, the temperature on the ceiling side becomes higher than the set indoor temperature, and if cooling is continued, the temperature on the floor side becomes lower than the set indoor temperature.

[0003] Therefore, there is a proposal to solve the loss of energy, by detecting a difference in the upper and lower temperatures in the room, and stirring the indoor air when the temperature difference exceeds a set value (Japanese Patent Application Laid-Open (JP-A) No. 5-180459).

[0004] According to the known invention, since the temperature difference between the upper part and the lower part of the room is detected, and a convection is generated in the room, the loss of energy in air conditioning, such that high-temperature air is accumulated near the ceiling and low-temperature air is accumulated in the vicinity of the floor, can be improved. However, energy saving by using the process together with the conventional air conditioner is not taken into consideration. Moreover it is not taken into consideration to control the power supplied to a fan for generating the convection in the room, based on the size of the temperature difference between the upper part and the lower part of the room. Furthermore, it is not taken into consideration to control the feed rate of energy (for example, the quantity of power, gas, fuel oil or the like) to the air conditioner installed in the room.

[0005] When the indoor space is large (for example, in offices, stores, assembly halls, public office buildings, schools, hospitals, factories, greenhouses, etc.), it is necessary to provide a large number of air supply and exhaust openings, in order to generate the convection in the indoor air. However, opening and closing control of the large number of air supply and exhaust openings or control of flow rate at the time of supplying or exhausting the air is not suggested at all.

DISCLOSURE OF THE INVENTION

[0006] An object of the present invention is to save energy in indoor air conditioning by combining indoor air vertical convention producing means with indoor air conditioning means.

[0007] In other words, in the invention, a fan for performing suction and exhaust of the air for vertically circulating the indoor air through suction and exhaust ports provided on upper and lower parts in a room is operated or stopped, according to a difference in temperatures detected on the upper and lower parts of the room, and the output of the fan during operation is increased or decreased according thereto, so as to prevent a loss of energy such that warm air is accumulated on the upper part in the room, and cool air is accumulated on the lower part in the room.

[0008] Further in the invention, the operation or suspension of an air conditioner installed indoors, and the amount of energy consumed at the time of operating the air conditioner is controlled depending on a difference between a temperature detected in the room and a preset indoor temperature.

[0009] By combining the indoor air vertical convection producing means and the indoor air conditioning means, room temperature can be controlled efficiently with less energy consumption.

[0010] That is, with an energy saving method in indoor air conditioning, proposed by the present invention, air is sucked or exhausted from the upper part and the lower part of the room, according to a temperature difference between the temperature on the upper part and the temperature on the lower part of the room, to vertically circulate the indoor air, and the air conditioner equipped in the room is operated or stopped, according to a temperature difference between the indoor temperature and the preset indoor temperature.

[0011] For example, the temperatures on the upper part and the lower part of the room are compared with each other, and when a temperature difference between those temperatures becomes a predetermined set temperature difference, air is sucked or exhausted from the upper part and the lower part of the room, to vertically circulate the indoor air, and when the indoor temperature is compared with the preset indoor temperature and there is a temperature difference, the air conditioner equipped in the room is operated or stopped.

[0012] By vertically circulating the indoor air by sucking or exhausting the air from the upper part and the lower part of the room, the temperature difference between the upper part and the lower part of the room is suppressed to the predetermined set temperature difference or below, and a loss of energy such that warm air is accumulated on the upper part in the room, and cool air is accumulated on the lower part in the room can be prevented.

[0013] In this manner, the temperature difference between the upper part and the lower part of the room is suppressed to the predetermined set temperature difference or below. Further, the indoor temperature is compared with the preset indoor temperature, and only when there is a temperature difference between the indoor temperature and the preset indoor temperature, the air conditioner equipped in the room is operated or stopped, thereby enabling efficient control of the room temperature, with less energy consumption.

[0014] The temperature on the upper part of the room is detected at one point or a plurality of points near the ceiling, and the temperature on the lower part of the room is detected at one point or a plurality of points near the floor.

[0015] Moreover, the suction rate or exhaust rate of air from the upper and lower parts of the room can be increased or decreased, based on the size of a difference between the detected temperature difference between the upper part and the lower part of the room and the set temperature difference, and the amount of energy consumed for the operation of the air conditioner can be increased or decreased, based on the size of a difference between the detected indoor temperature and the set indoor temperature.

[0016] For example, when a difference between the detected temperature difference between the upper part and the lower part of the room and the set temperature difference is large, the suction rate or the exhaust rate of the air from the upper part and the lower part of the room is increased, to thereby increase the speed of the vertical convection of air caused in the room. As a result, the temperature difference between the upper part and the lower part of the room can be efficiently suppressed to the predetermined set temperature difference or below- on the other hand, when the above difference is small, even if the suction rate or the exhaust rate of the air from the upper part and the lower part of the room is decreased, to reduce the speed of the vertical convection of air caused in the room, since the above difference is small, it is easy to suppress the temperature difference between the upper part and the lower part of the room to the predetermined set temperature difference or below. Therefore, in this manner, room temperature can be efficiently adjusted, while suppressing the energy consumption.

[0017] When there is a difference between the detected indoor temperature and the set indoor temperature, and the air conditioner is to be operated, the amount of energy consumed for the operation of the air conditioner, more specifically, the amount of power to be supplied, or the amount of gas or fuel oil consumed for the operation of the air conditioner is increased or decreased, depending on the size of the difference between the detected indoor temperature and the set indoor temperature. As a result room temperature can be efficiently adjusted, while suppressing the energy consumption.

[0018] Further, suction or exhaust of air from the upper and lower parts of the room may be respectively carried out at a plurality of points on the upper and lower parts of the room, detection of the temperature on the upper and lower parts of the room may be performed at the plurality of suction or exhaust points of the air, and the suction rate or the exhaust rate of the air may be increased or decreased at the plurality of respective points where suction or exhaust of air is being carried out.

[0019] As a result, even when the indoor space is large (for example, in offices, stores, assembly halls, public office buildings, schools, hospitals, factories, greenhouses, etc.), vertical convection can be produced in the indoor air, and a vertical temperature difference in such a large indoor space can be eliminated efficiently.

[0020] The next invention is an energy saving apparatus in indoor air conditioning, comprising indoor air vertical convection producing means and indoor air conditioning means, respectively having a construction described below.

[0021] The indoor air vertical convection producing means comprises air suction and exhaust ports respectively provided on the upper and lower parts of the room; a duct for connecting the suction and exhaust ports; a fan placed in the intermediate of the duct, which can change over the air blasting direction; first and second temperature sensors for detecting the temperature on the upper part and the temperature on the lower part of the room, respectively; and a first control unit which receives the input from the first and second temperature sensors and controls the operation of the fan corresponding to the temperature difference between the upper part and the lower part of the room.

[0022] For example, control of the first control unit is carried out in such a manner that when the temperatures on the upper part and the lower part of the room are compared, and the temperature difference between these exceeds a predetermined set temperature difference, the fan is operated to suck or exhaust air from the upper part and the lower part of the room to thereby vertically circulate the indoor air. On the other hand, when the temperature difference between these falls below the predetermined set temperature difference, the operation of the fan is stopped.

[0023] The indoor air conditioning means comprises: an air conditioner equipped in the room; a third temperature sensor for detecting the indoor temperature; and a second control unit which receives the input from the third temperature sensor and controls the operation of the air conditioner corresponding to the indoor temperature.

[0024] For example, when the indoor temperature detected by the third temperature sensor is compared with the predetermined set indoor temperature, and there is a temperature difference therebetween, control of the second control unit is carried out so as to operate or stop the air conditioner equipped in the room.

[0025] In the apparatus of the present invention described above, the configuration may be such that a plurality of structures comprising: air suction and exhaust ports respectively provided on the upper and lower parts of the room; and a duct for connecting the suction and exhaust ports, having a fan that can change over the air blasting direction placed in the intermediate thereof, is installed at a plurality of points in the room, and the first and second temperature sensor for respectively detecting the temperature on the upper part and the temperature on the lower part of the room is provided for each structure, so that the operation of the fan is controlled by the first control unit for each fan in the plurality of structures.

[0026] In this manner, even when the indoor space is large (for example, in offices, stores, assembly halls, public office buildings, schools, hospitals, factories, greenhouses, etc.), vertical convection can be produced in the indoor air, and a vertical temperature difference in such a large indoor space can be eliminated efficiently.

[0027] In the present invention described above, when the upper and lower suction and exhaust ports are connected by the duct, and the fan is placed in the duct, the apparatus can be one installed indoors. Moreover, when a house is newly built, a duct having a fan placed therein can be accommodated under the roof.

[0028] Furthermore, the present invention can be employed in assembly halls, schools, hospitals, public office buildings, factories, greenhouses, etc. (that is, in a place having a wide indoor space) as well as in ordinary houses, regardless of the size of the indoor space. In the case of a wide indoor space, the apparatus can be designed in an efficient system, such that the suction and exhaust ports and the temperature sensors are arranged in a plurality of points, and opening or closing of the suction and exhaust ports is separately controlled.

[0029] In the present invention, not only the energy is saved by taking a balance of temperature between the upper and lower parts of the room, but also the amount of power used for the fan, and the energy source, such as power, gas or fuel oil used for the air conditioner, can be reduced, thereby the energy can be saved comprehensively. According to experiments in ordinary houses, energy saving of about 30% can be recognized by applying the present invention.

[0030] In the present invention, since air is circulated inside the duct in order to vertically circulate the indoor air, this can be used for cleaning of the air (by allowing air to pass through a filter), for adjusting the humidity or for sterilization. Particularly, removal of No₂, CO₂ or other harmful gasses, and positive improvement of the air, such as mixing minus ions, can be easily performed.

[0031] The present invention is constructed such that temperatures on the upper and lower parts of the room are measured, to drive the fan depending on the temperature difference, air is sucked or exhausted from suction and exhaust ports provided on the upper and lower parts of the room to vertically circulate the indoor air, to thereby eliminate (or reduce) the temperature difference between the upper part and the lower part in the indoor temperature, and the air conditioner and the fan are operated with less energy, in order to adjust the indoor temperature to a preset indoor temperature.

[0032] The driving of the fan and the operation of the air conditioner are performed automatically and with less energy, for example, by placing an inverter in a circuit, or the like.

[0033] The apparatus of the present invention is independently installed indoors, or installed on the wall or under the roof, at the time of building a new building. Therefore, needless to say, it can be newly installed, and further it can be used together with an existing air conditioner, or the existing air conditioner can be slightly modified and used. The method of the present invention can be employed in from ordinary houses having a small indoor capacity, to for example assembly halls, schools, hospitals, public office buildings, factories or greenhouses having a large capacity.

[0034] According to the present invention, when the temperature difference between the upper part and the lower part of the room exceeds a predetermined set temperature difference, vertical air convection is produced in the room to make the indoor temperature uniform on the upper and lower parts of the room. Moreover, the actual room temperature at this time is compared with the predetermined set room temperature, to adjust the room temperature. As a result, there is a large energy savinq effect.

[0035] Furthermore, energy saving operation is carried out by increasing or decreasing the operation output of the fan and the air conditioner, depending on the size of the temperature difference. As a result, there is a large energy saving effect as a whole.

BRIEF DESCRIPTION OF DRAWINGS

[0036]FIG. 1 is a block diagram for explaining an operating process in the method of the present invention;

[0037]FIG. 2 is an elevational view for explaining the construction of a preferable embodiment of the apparatus according to the present invention;

[0038]FIG. 3 is a plan view of FIG. 2;

[0039]FIG. 4 is an elevational view for explaining the construction of another preferable embodiment of the apparatus according to the present invention;

[0040]FIG. 5 is a plan view of FIG. 4;

[0041]FIG. 6A is a diagram showing an electric circuit of a fan;

[0042]FIG. 6B is a circuit diagram of an air conditioner;

[0043]FIG. 7A is a longitudinal sectional view for explaining an other embodiment of indoor air vertical convection producing means, with a part omitted;

[0044]FIG. 7B is an front elevational view of FIG. 7A;

[0045]FIG. 8A is a graph for explaining the execution state of the apparatus of the present invention at the time of cooling; and

[0046]FIG. 8B is a graph for explaining the execution state of the apparatus of the present invention at the time of heating.

BEST MODE FOR CARRYING OUT THE INVENTION

[0047] [First Embodiment]

[0048] Energy saving apparatus in indoor air conditioning according to the present invention will be described, with reference to FIGS. 2 and 3.

[0049]FIG. 2 is an elevational view showing the state in which an example of the apparatus according to the present invention is provided on a ceiling 6 and walls 7 in a room 1, and FIG. 3 is a plan view thereof.

[0050] As shown in FIGS. 2 and 3, ducts 4 a, 4 a, 4 a, 4 a are arranged in a standing condition along the walls 7, at four corners of the room in a building, and a suction and exhaust port 3 for the lower air is respectively provided at the lower part of each duct 4 a, facing indoors in the vicinity of the floor 8.

[0051] The upper ends of the respective ducts 4 a, 4 a, 4 a, 4 a provided at four corners of the room protrude to the upper side of the ceiling 6. The upper ends of the respective ducts 4 a, 4 a, 4 a, 4 a are connected to collecting ducts 4 c, 4 c on the opposite sides, via a plurality of branched ducts 4 b, on the upper side of the ceiling 6, and the opposite collecting ducts 4 c are connected to a main duct 4 d, provided in the middle of the ceiling A fan 5 is placed in the middle of the main duct 4 d. An open end of the main duct 4 d is connected to a suction and exhaust grill 9, set on the ceiling 6. A suction and exhaust port 2 for the upper air is provided in this suction and exhaust grill 9.

[0052] A filter is detachably provided in the suction and exhaust port 2 in the suction and exhaust grill 9, thereby dust and dirt in the room are forcibly removed, to supply clean air to the room.

[0053] In FIGS. 2 and 3, ducts 4 a to 4 d are used both as ducts for warm air and ducts for cold air. The lower suction and exhaust port 3 serves as a suction port and an exhaust port, and the upper suction and exhaust port 2 serves as a suction port and an exhaust port, depending on the rotation direction of the fan 5.

[0054] For the fan 5, a blower (fan) for ducts is used, which is of a type that performs normal rotation and reverse rotation by switching control. For this blower for ducts, a normal single propeller blower may be used, or one referred to as a counter rotation blower, which realizes low noise, may be used.

[0055] The counter rotation blower shown in FIGS. 2 and 3 is a counter-rotating blower, and the structure thereof is such that a first propeller 11 which rotates in the air blasting direction, and a second propeller 12 which rotates in the opposite direction, with a space in the axial direction with respect to the propeller 11, are provided inside a cylindrical case 10 connected to the middle of the main duct 4 d. By rotating motors 13, 14 provided in the propellers 11 and 12, the rotational flow by the first propeller 11 is rectified to the axial flow by the second propeller 12, and the rotational energy is converted into pressure energy. As a result, highly efficient static pressure can be obtained.

[0056] As shown in FIG. 2, an upper temperature sensor S1, being a first temperature sensor provided on the upper part of the room, is provided on the ceiling 6 side, and a lower temperature sensor S2, being a second temperature sensor provided on the lower part of the room, is provided on the wall near the floor 8.

[0057] These upper temperature sensor S1 and the lower temperature sensor S2 may be provided one each on the ceiling 6 side and on the floor 8 side, or may be provided in a plurality of numbers. The arranged number thereof can be adjusted according to the size of the indoor space and the number of the suction and exhaust ports 2 for the upper air and the number of the suction and exhaust ports 3 for the lower air.

[0058] The fan 5, the upper temperature sensor S1 and the lower temperature sensor S2 are respectively connected to a controller 15, being a first control unit, by wiring (not shown).

[0059] The controller 15 has a fan circuit having the control structure described below, thereby enabling the following control. One is a control for operating or stopping the fan 5, respectively, when a difference between the upper temperature and the lower temperature of the room actually detected by the upper temperature sensor S1 and the lower temperature sensor S2 exceeds or falls under a predetermined set temperature difference. The other control is for controlling the size (strength) of the operation output of the fan 5, depending on the size of a difference between the difference between the upper temperature and the lower temperature of the room actually detected by the upper temperature sensor S1 and the lower temperature sensor S2, and the predetermined set temperature difference.

[0060] The controller 15 may perform switching by remote control.

[0061] The control structure of the fan circuit in the controller 15 will be described, with reference to FIG. 6A. A relay coil A is connected to a vertical temperature detector, to which the upper temperature sensor S1 and the lower temperature sensor S2 are connected, and these are connected to a power source (DC24V). When the temperature difference detected by the upper temperature sensor S1 and the lower temperature sensor S2 exceeds the predetermined set temperature difference, electric current flows into the relay coil A, to close a contact point a1. In other words, the contact point a1 is turned ON. On the other hand, when the temperature difference detected by the upper temperature sensor S1 and the lower temperature sensor S2 falls below the predetermined set temperature difference, electric current does not flow into the relay coil A, to thereby open the contact point a1. In other words, the contact point a1 is turned OFF.

[0062] Moreover, the contact point a1 is connected to a fan motor FM that rotates the fan 5 (for example, connected to the circuit via an inverter), and make and break of the electric current of the power source (AC100V) is carried out at the contact point a1, as described above. As a result, when the contact point a1 is closed (that is, turned ON), the motor FM of the fan 5 rotates, and the motor FM of the fan 5 stops when the contact point a1 is opened (that is, turned OFF).

[0063] The indoor air vertical convection producing means is formed in the above-described construction.

[0064] On the other hand, an air conditioner 16 is installed on the indoor wall. The air conditioner 16 is generally available in the market, which blows cold air or warm air indoors depending on the input signal. This air conditioner 16 is connected to the electric circuit of the fan 5 described above (for example, connected to the circuit via an inverter).

[0065] The electric air conditioning circuit of the air conditioner 16 is such that, as shown in FIG. 6B, a contact point a2 is connected with a contact point a3 via an air conditioner operation switch SW connected to the power source (AC100V), and a compressor motor MC is further connected thereto via a temperature controller having an air conditioner set temperature sensor S3. In other words, such an electric air conditioner circuit shown in FIG. 68 corresponds to a second control unit that controls the operation and suspension of the air conditioner 16. The air conditioner set temperature sensor S3 corresponds to a third temperature sensor for detecting indoor temperature.

[0066] The indoor air conditioning means is formed in the above-described construction.

[0067] For example, when the fan motor FM in the fan circuit is turned ON, the compressor motor MC operates by means of the contact point a2, and when the fan motor FM in the fan circuit is turned OFF, the compressor motor MC operates by means of the contact point a3.

[0068] By having such a construction, for example, when the air conditioner 16 is set as heating means, and if the air conditioner operation switch SW is turned ON (manually), the compressor motor MC is stopped by the temperature controller, when the indoor temperature detected by the air conditioner set temperature sensor S3 has reached the predetermined set indoor temperature, and if the indoor temperature does not reach the set temperature, the compressor motor MC is operated by the temperature controller.

[0069] Therefore, in the temperature controller (second control unit) in the air conditioner circuit, for example, the predetermined set indoor temperature is 26° C., the air conditioner operates until the air conditioner set temperature sensor S3 senses 26° C.

[0070] On the other hand, the fan 5 continues to operate until there is no temperature difference in the temperature detection results of the upper temperature sensor S1 and the lower temperature sensor S2, which sense the upper temperature and the lower temperature in the room. As a result, the indoor temperature can be maintained at 26° C. vertically uniformly, such that there is little temperature difference between the upper and lower parts of the room.

[0071] In other words, in the wintertime, the air conditioner 16 set as heating means operates, until the temperature sensor S3 on the air conditioner circuit side (third temperature sensor) senses for example 26° C., which is the set indoor temperature. At this time, the fan 5 is rotated so as to blow air from the ceiling 6 side to the floor 8 side, to suck warm air accumulated in the upper part of the room from the suction and exhaust port 2 on the ceiling 6 side, and exhaust it from the suction and exhaust ports 3 on the floor 8 side as warm wind. As a result, the floor 8 side can be efficiently warmed to make the indoor temperature uniform as a whole.

[0072] Also in the summertime, the air conditioner 16 set as cooling means operates, until the temperature sensor S3 on the air conditioner circuit side (third temperature sensor) senses for example 22° C., which is the set indoor temperature. At this time, the fan 5 is rotated so as to blow air from the floor 8 side to the ceiling 6 side, to suck cool air accumulated in the lower part of the room from the suction and exhaust ports 3 on the floor 8 side, and exhaust it from the suction and exhaust port 2 on the ceiling 6 side as cold wind. As a result, the floor 6 side can be efficiently cooled to make the indoor temperature uniform as a whole.

[0073] An inverter (not shown) is built in the circuit of the fan motor FM (FIG. 6A), in the electric air conditioning circuit of the air conditioner 16 (FIG. 6B), in the circuit of the compressor motor MC and the like. As a result, the fan 5 and the air conditioner 16 are fully operated or operated at a reduced speed to save energy, respectively, depending on the size of a difference between the difference between the upper temperature and the lower temperature actually detected by the upper temperature sensor S1 and the lower temperature sensor S2, and the predetermined set temperature difference, and depending on the size of a difference between the indoor temperature actually detected by the temperature sensor S3 (third temperature sensor) and the predetermined set indoor temperature.

[0074] In the above-described construction, if the construction is such that the air conditioner temperature sensor S3 provided in the air conditioner 16 is connected to the upper temperature sensor S1 and the lower temperature sensor S2, so that even when there is no temperature difference between the upper part and the lower part of the room, when the air conditioner temperature sensor S3 has not reached the set temperature, the fan 5 is rotated upon operation of the air conditioner, it is more preferable for controlling the temperature, while keeping the indoor temperature vertically uniform.

[0075] The fan 5 shown in FIGS. 2 and 3 can be used both as the duct 4 for warm wind and the duct 4 for cold wind. However, the indoor air vertical convection producing means shown in FIGS. 4 and 5 has a construction suitable for a relatively large indoor space, by providing a duct for warm wind and a duct for cool wind separately.

[0076] That is to say, it is the same as the above-described construction that ducts 4 a, 4 a, 4 a, 4 a are arranged in a standing condition along the walls 7 at four corners of the room. However, as shown in FIG. 5, the respective ducts 4 a, 4 a, 4 a, 4 a are connected to branched ducts 4 b, 4 b, 4 b, 4 b at the upper ends, to connect the four sides. The branched ducts 4 b, 4 b, 4 b, 4 b are connected to collecting ducts 4 c, 4 c on the opposite sides, respectively, in the middle thereof. Moreover, the opposite collecting ducts 4 c, 4 c, 4 c, 4 c are connected to a main duct 4 d 1 for warm wind and a main duct 4 d 2 for cold wind. A fan 5 is respectively provided in the main ducts 4 d 1 and 4 d 2. The open end of each main duct 4 d 1, 4 d 2 is connected to a suction and exhaust grill 9 set on the ceiling 6. As a result, the duct 4 d 1 on the side shown by oblique lines is designated as a duct exclusive for warm wind, and the other duct 4 d 2 is designated as a duct exclusive for cold wind.

[0077] Other construction is the same as the embodiment shown in FIGS. 1 and 2, but in the duct construction shown in FIGS. 4 and 5, the rotation direction of the respective fans 5, 5 can be fixed for both in the wintertime and the summertime. Also, in the duct construction shown in FIGS. 4 and 5, a large filter 17 is provided in the middle of the main duct 4 d 2, in addition to the filter provided in the suction and exhaust grill 9.

[0078] [Second Embodiment]

[0079] An embodiment of an energy saving method in indoor air conditioning according to the present invention, which uses the energy saving apparatus in indoor air conditioning of the present invention described above with reference to FIGS. 2 through 4, will be described, with reference to FIG. 1.

[0080] The output of the two temperature sensors respectively installed on the upper part (near the ceiling) and on the lower part (near the floor) of the room is input to the first control unit. When a temperature difference between the two temperature sensors has reached the set temperature difference (for example, 1° C.), the first control unit outputs to the fan 5 to drive the fan 5. As a result, the air in the ducts 4 a connecting the suction and exhaust ports 2 and 3 provided on the upper part and the lower part of the room is made to flow upwards or downwards. For example, at the time of heating, the fan 5 rotates so as to shift the high-temperature air on the ceiling side of the room towards the floor side.

[0081] When it is assumed that the predetermined set indoor temperature is 20° C., and temperature control is to be carried out towards this set indoor temperature, and if the temperature sensor on the ceiling side detects 18° C., and the temperature sensor on the floor side detects 16° C., the fan 5 rotates so that the air sucked from the suction and exhaust port 2 on the ceiling side comes down in the ducts 4 a, and exhausted from the suction and exhaust ports 3 on the floor side.

[0082] As a result, the temperature of the air on the floor side rises, and the indoor air can be efficiently temperature-controlled by the convection.

[0083] As described above, as a result of temperature control, when the indoor temperature becomes 17° C., and there is no temperature difference (not larger than 1° C.) between the temperature detected by the upper temperature sensor and the temperature detected by the lower temperature sensor, the first control unit outputs for stopping the fan, and hence the fan 5 stops.

[0084] On the other hand, when the temperature sensor in the air conditioner 16, which is set as a heater, detects 17° C., the air conditioner 16 starts due to the output of the control unit in the air conditioner 16, to thereby blow humidified air (for example, 25° C.) into the room.

[0085] In this manner, when the humidified air is blown into the room, this humidified air goes up towards the ceiling, while warming the nearby air. When the humidified air is accumulated in the vicinity of the ceiling, the temperature near the ceiling becomes, for example, 22° C. As a result, since there is a big difference between the temperature on the floor side, that is 17° C., and the temperature near the ceiling, the fan 5 starts again.

[0086] As described above, the indoor air is circulated so that the room temperature rises quickly up to about 19° C., and when the temperature difference between the temperature detected by the upper temperature sensor and the temperature detected by the lower temperature sensor becomes not larger than 1° C., the fan 5 stops.

[0087] Also in this case, since the indoor temperature is 19° C., and it is lower than the set indoor temperature, 20° C., the air conditioner 16 continues to exhaust warm air of 25° C.

[0088] When the temperature sensor on the ceiling side detects 21° C., since the temperature sensor on the floor side has detected 19° C., the fan 5 starts again.

[0089] In this manner, the room temperature, which has been 16° C. initially, sequentially rises to 18° C. and then 19° C., with substantially no temperature difference between the upper and lower parts of the room, and when the room temperature reaches the set indoor temperature, 20° C., the air conditioner 16 also stops.

[0090] Here, for example, if the temperature of the indoor temperature adjacent to the window drops, the air falls and is accumulated on the floor side, and becomes for example 19° C.

[0091] In this case, since the temperature on the ceiling side is 20° C., the temperature difference becomes 1° C. The fan 5 starts due to the output from the control unit, to suck the upper air and blow it downwards, and hence the indoor air is averaged quickly (for example, 19.5° C.). As a result, the air conditioner 16 starts, to blow the humidified air of 25° C. again, to increase the temperature of the indoor air, and when the temperature becomes 20° C., the air conditioner 16 stops.

[0092] In the above case, the output to the fan 5 can be changed, for a case where the temperature difference between the upper temperature sensor and the lower temperature sensor is 4° C., and for a case where the temperature difference there between is 1° C. For example, when the temperature difference is 5° C., the fan 5 is rotated with 100% output, but when the temperature is 1° C., the fan 5 is rotated with 20% output. Similarly, when the room temperature is 5° C. lower than the set indoor temperature, the air conditioner 16 set as a heater is operated at 100% full capacity, but when the room temperature is lower than the set indoor temperature only by 1° C., the air conditioner 16 is operated at 20% output.

[0093] In this manner, a loss of energy such that high-temperature air is accumulated on the ceiling side, and low-temperature air is accumulated on the floor side can be prevented. At the same time, the air conditioner is efficiently operated, enabling reasonable adjustment of the room temperature. Further, the room temperature can be adjusted, while saving the energy, by controlling and using the output of the fan and the air conditioner in the range of from 100% to 20%.

[0094] As described above, energy saving of about 15 to 25% can be achieved, by vertically circulating the indoor air, and by using the air conditioner, which is operated when the indoor temperature is away from the predetermined set indoor temperature. Moreover, energy saving of about 15 to 5% can be achieved by operation control for adjusting the output of the fan and the air conditioner.

[0095] [Third Embodiment]

[0096] In this embodiment, the indoor air vertical convection producing means described in the second embodiment is housed in one housing, and hence indoor construction work is not necessary, and it may be a movable type, which is arranged on the floor 8 in the room (FIGS. 7A and 7B).

[0097] The construction is such that an upper suction and exhaust grill 9 a and a lower suction and exhaust grill 9 b are provided respectively on the upper and lower positions of the housing 18, the upper suction and exhaust grill 9 a being the upper suction and exhaust port 2, and the lower suction and exhaust grill 9 b being the lower suction and exhaust port 3, and a duct 4 is vertically provided for connecting the upper and lower suction and exhaust ports 2 and 3. A fan 5 that can change over the normal rotation and reverse rotation is provided in the middle of the duct 4. Moreover, an upper temperature sensor S1 is provided on the upper part of the housing 18, and a lower temperature sensor S2 is provided on the lower part of the housing 18.

[0098] In such a construction, the height of the housing 18 and the length of the duct 4 should be designed, based on the height of the ceiling of the indoor space in which the housing is to be installed. When the height of the housing 18 is high, overturning can be prevented by fixing the housing 18 on the wall or the like.

[0099] In this construction, the upper temperature sensor S1 and the lower temperature sensor S2 may be provided near the ceiling 6 and near the floor 8 of the room, respectively, such that the respective temperature sensors are guided to a controller 15 provided in the housing 18 by wiring.

[0100] A filter 19 is detachably provided inside of the upper and lower suction and exhaust grills 9 a and 9 b, so as to remove dust and dirt in the room and supply clean air.

[0101] In the above construction, the duct 4 is a dual-purpose type for warm wind and cold wind. At the time of heating in the wintertime, when the upper temperature sensor S1 and the lower temperature sensor S2 detect a temperature difference, the fan 5 rotates so as to flow air from the upper part to the lower part. As a result, the warm air accumulated on the upper part of the room is sucked from the upper suction and exhaust port 2 in the upper suction and exhaust grill 9 a and exhaust it as warm wind from the suction and exhaust port 3 in the lower suction and exhaust grill 9 b, to thereby warm the floor 8 side. As a result, the overall indoor temperature can be made uniform efficiently.

[0102] Further, at the time of cooling in the summertime, when the upper temperature sensor S1 and the lower temperature sensor S2 detect a temperature difference, the fan 5 rotates so as to flow air from the lower part to the upper part. As a result, the cold air accumulated on the lower part of the room is sucked from the lower suction and exhaust port 3 in the lower suction and exhaust grill 9 b and exhaust from the suction and exhaust port 2 in the upper suction and exhaust grill 9 a as cold wind, to thereby cool the ceiling 6 side. As a result, the overall indoor temperature can be made uniform efficiently.

[0103] In this embodiment, only the vertical convection in the indoor air has been described. In this embodiment, however, when an existing air conditioner 15 has been already installed in the room, and as a result of the vertical convection in the indoor air, the vertically averaged room temperature is different from the set indoor temperature, the air conditioner 16 is automatically driven, as described in the first embodiment.

[0104] In this case, it is the same as in the first embodiment that large energy saving can be achieved by adjusting the output of the fan 5 and the air conditioner 16, the driving force of the fan motor, and the generated quantity of heat of the air conditioner (exothermic and endothermic), based on the size of a difference between the difference between the upper temperature and the lower temperature of the room actually detected by the upper temperature sensor S1 and the lower temperature sensor S2, and the predetermined set temperature difference, and based on the size of a difference between the actual indoor temperature detected by the temperature sensor S3 (third temperature sensor) and the predetermined set indoor temperature.

[0105]FIGS. 8A and 8B are graphs showing the execution state of the indoor air vertical convection producing means and the air conditioner, when the method and apparatus for saving energy in indoor air conditioning according to the present invention are used.

[0106] The indoor air vertical convection producing means was operated for 10 hours in total, from 6 to 9, from 11 to 14, and from 18 to 22, of a day. In this case, at the time of cooling for decreasing the indoor temperature from 27° C. to 26° C., the oblique portions in FIG. 8A show the operated hour of the air conditioner, which is set as the cooling means. Moreover, at the time of heating for increasing the indoor temperature from 25° C. to 26° C., the oblique portions in FIG. 8B show the operating time of the air conditioner, which is set as the heating means. In other words, it can be confirmed that the operating time of the air conditioner has been reduced. 

1. An energy saving method in indoor air conditioning, comprising: a step of vertically circulating indoor air by sucking or exhausting air from the upper and lower parts of the room, depending on a temperature difference between the upper temperature and the lower temperature in the room; and a step of operating or stopping an air conditioner equipped in the room, depending on a temperature difference between the indoor temperature and a predetermined set indoor temperature.
 2. An energy saving method in indoor air conditioning according to claim 1, wherein the upper temperature in the room is detected at one or a plurality of points near the ceiling, and the lower temperature in the room is detected at one or a plurality of points near the floor.
 3. An energy saving method in indoor air conditioning according to any one of claim 1 and claim 2, wherein the suction rate or exhaust rate of the air from the upper and lower parts of the room is increased or decreased, based on the size of a difference between a detected temperature difference between the upper and lower parts of the room and the set temperature difference, and the energy quantity used for the operation of the air conditioner is increased or decreased, based on the size of a difference between the detected indoor temperature and the set indoor temperature.
 4. An energy saving method in indoor air conditioning according to claim 3, wherein suction or exhaust of the air from the upper and lower parts of the room is carried out at a plurality of points on the upper and lower parts of the room, and detection of temperatures on the upper and lower parts of the room is carried out at the plurality of suction or exhaust points of the air, and increase or decrease of the suction rate or exhaust rate of the air is carried out at the respective points where the suction or exhaust of the air is carried out.
 5. An energy saving apparatus in indoor air conditioning, comprising: indoor air vertical convection producing means comprising: air suction and exhaust ports respectively provided on the upper and lower parts of the room; a duct for connecting the suction and exhaust ports; a fan placed in the intermediate of the duct, which can change over the air blasting direction; first and second temperature sensors for detecting the temperature on the upper part and the temperature on the lower part of the room, respectively; and a first control unit which receives the input from the first and second temperature sensors and controls the operation of the fan corresponding to a temperature difference between the upper part and the lower part of the room; and indoor air conditioning means comprising: an air conditioner equipped in the room; a third temperature sensor for detecting the indoor temperature; and a second control unit which receives the input from the third temperature sensor and controls the operation of the air conditioner corresponding to the indoor temperature.
 6. The energy saving apparatus in indoor air conditioning according to claim 5, wherein a plurality of structures comprising: air suction and exhaust ports respectively provided on the upper and lower parts of the room; and a duct for connecting the suction and exhaust ports, having a fan that can change over the air blasting direction placed in the intermediate thereof, is installed at a plurality of places in the room, and the first and second temperature sensors for respectively detecting the temperature on the upper part and the temperature on the lower part of the room are provided for each structure, so that the operation of the fan is controlled by the first control unit for each fan in the plurality of structures. 